What are the Common Overwintering Insects in St. Louis?

Author: Mosquito Squad of West St. Louis County

Some insects can’t survive winter. Other’s find their way into your home or other nesting space to hunker down and wait it out. In St. Louis, this can mean an invasion of your home. These pests find the tiniest crevices, holes in screens, faucets, drains, and other hidden ways to get indoors. We urge you to consider a pest control winterization service from our pros. But, we also want you to know what type of insects you are most likely to encounter in your home this winter.

Pill Bugs – Roly-Polys

Pill bugs, also known as roly-polys because of their defense mechanism of rolling up like an armadillo, prefer dark and moist places. While they are known as “pill bugs” they are actually closer in relation to crustaceans than insects. They can survive winter temperatures but will often make their way into our homes to avoid the extreme cold.

Stink Bugs

Stink bugs are easy to identify due to their shield-shaped brown body. The light markings on the outer edges look like turtle shells. Stink bugs can be destructive to crops and gardens; however, for homeowners, they are usually just annoying for the unpleasant odor they emanate.

Boxelder Bugs

If you’ve seen one boxelder bug, you’ve seen many. They tend to infest buildings in alarmingly large numbers. They prefer trees, but in the fall, you may find them in mass numbers covering the south-facing side of buildings. Like stink bugs, boxelder bugs are not harmful to humans, just to the trees they live in. Nonetheless, their mass quantity and invasive habits make them a nuisance to St. Louis homeowners.

Asian Lady Beetles

Otherwise known as ladybugs, these round, spotted insects can be found in an array of colors, including yellow, orange, red, pink, and black. As a defense mechanism, they can excrete an odorous yellow fluid that might stain. Lady bugs can cause asthma or allergic reactions in some but are not generally a threat to humans or other animals. They will often inhabit homes and other buildings to seek refuge from the cold during winter.

Cluster Flies

Slightly larger than a housefly, you likely mistake these insects for house flies. They are dull gray in color with golden hairs on their thorax. These insects also like the south side or sunny side of buildings and even get in the windows for warmth in the winter. Not dangerous, but obnoxious.

Brown Recluse Spiders

Light brown and the size of a quarter, brown recluse spiders have a distinct eye pattern. Whereas most spiders have eight eyes arranged in two rows of four. Brown recluse spiders have six eyes arranged in pairs. One set centered in front and the other two sets behind and to the sides. Brown recluse spiders will stay hidden away in undisturbed places such as closets, boxes, crawl spaces, and basements.

Some people may have a bad reaction to brown recluse bites, but most of the time the bite simply requires basic medical attention and heals fine. It is rare to come across a brown recluse because they hide so well.

Paper Wasps

Paper wasps like to build their nests in porch ceilings, soffits, door and window frames, and other protected surfaces. The main population won’t be very threatening if they get indoors during the winter. However, the queen will find a place to overwinter and start a new nest in the spring. Keeping the queen out of your house in winter is a great first step in avoiding a nest come spring.

Preventing Overwintering Pests

Overwinter insects can be gross and disturbing. While most are not harmful to you or your home, the annoyance factor is critical to address for quality of life. Any insect that overwinters in your home is the main source of what can become a huge population of the annoying insects come spring and summer. Whether it is ants, flies, wasps, spiders, mosquitoes, or ticks that are bugging you – make sure you take preventative measures to keep them out of your home in the winter to help reduce the outdoor annoyance come spring.

A few things you can do yourself include repairing holes in screens, checking for tiny entryways such as cracks in your foundation or separations in your siding and filling them with caulk, clearing leaf and lawn debris away from your home’s foundation, and ensuring a tight seal around doors, windows, and utility entry points.

In addition, preventative pest control treatment each fall is crucial. At Mosquito Squad of West St. Louis and St. Louis Metro East, we offer an awesome pest control winter protection plan. It complements existing mosquito and tick control services or works excellent as a standalone. We focus on your lawn, landscape, and your home’s foundation to keep insects away from and out of the house. Call today to learn more.